Cushioning device for railroad cars



Dec. 27, 1938. o. c. DURYEA 2 141,521

CUISHQNING DEVICE FOR RAILROAD CARS Filed June 5, 1957 A 2 Sheets-Sheet 1 :Ummm/mlm. wml

ww a A e@ Ln I Mw) Dec. 27, 1938.. o. c. DURYEA v GUSHIONING DEVICE FOR RALROAD CARS 2 Sheets-'sheet 2 Filed June 5, 1957 Patented Dec. 27, 1938 UNITED STATES PATENT OFFIE CUSHIONING DEVICE FORl RAILROAD CARS Otho C; Duryea, Waterbury, Conn.

Application June 3, 1937, Serial No. 146,186

9 Claims.

This invention relates to improvements in cushioning devices for railroad cars and it consists of matters hereinafter described and more particularly pointed out in the appended claims.

5 One of the objects of the present invention is to produce a cushion device of this kind including longitudinally spaced sets of friction mechanisms and at least one spring for use in railroad cars and which, upon the imposition of a load or L pressure, yieldingly resists the same and absorbs the initial shock thereof, the spring upon release of load or pressure operating directly upon the end members of the device to' return said members to normal position Without functioning through the friction mechanisms.

Another object of the present invention is to provide a cushioning device of this kind including longitudinally spaced sets of friction mechanisms and a main cushioningrspring that is directly en- ;0 gaged with the end members of the device to return said members to the normal position upon the release of the load compressing the device.

A further object of the invention is to provide a cushioning device of this kind which compensates 5 in itself for manufacturing tolerances and consists of but a relatively few parts requiring little if any machine work and may be readily assembled so as to be produced at a relatively low cost.

Again, it is an object of the invention to pro- D vide a device of this kind that includes a pair of friction shoes with opposed friction surfaces and with which is associated means to increase the superficial areas of the opposedsurfaces.

The above-mentioned objects of the invention,

5 as well as others, together with the several advantages thereof, will more fullyappear as the specification proceeds.

In the drawings:

Fig. lis a longitudinal sectional View through a cushioning device for railroad cars embodying the preferred form of the invention, with the parts in their normal position when not under load.

Fig, 2 is a view similar to Fig. 1 with the parts in their load bearing position.

Fig. 3 is a transverse section through the device of Fig. 1 as taken on the line 3-3 of said Fig. 1.

Fig. 4 is a perspective view of one of the parts of the cushioning device.

Fig. 5 is a perspective view of a certain friction shoe or block embodied inthe device and which shoe Will be more fully referred to later.

The cushioning devices with which the present invention is more particularly concerned are those including friction mechanism and at least one spring for yieldingly resisting and gradually absorbing shocks and which may be used for draft gear and buffer purposes, as well as for snubbing the action of truck springs. For simplicity, the 5 invention is herein illustrated as embodied in a cushioning device for use in the draft gear of a railroad car. This is to be considered onlyby way of illustration and not by way of limitation.

Referring now in detail to that embodiment of 10 the invention illustrated in the drawings, I0 and II indicate respectively two load or pressure receiving members of a cushioning device adapted for use in the draft gear of a railroad car. As shown herein, both of these members are of the same shape and. form, being made from the same pattern. Each member I0 and I I includes a radial flange-like outer end' I2 and substantially semicylindrical body portion I3. The members Iii and I I are arranged with the body portion of one member facing endwise toward the flange of the other member, the body portions of both members being disposed in longitudinal overlapping relation and enclosing suitable friction mechanism as will later appear. In the outer end of V v each member I0 and II is an axial opening I2a whereby assembling of the parts of the cushioning device may be facilitated.

The body portion I3 of each member IIl-II is provided between its ends with a pair of internal tapering friction surfaces I4 and I5 respectively, arranged in tandem. These surfaces, which taper in the same direction, have substantially the same angle of taper. Each body portion, as best shown in perspective Fig. 4, is formed with an annular shoulder I6 at the outer end of the surface I5. Each of the internal tapering friction surfaces Ill- I5 is curved transversely, the ends of said surfaces being of the same radius but struck from different centers, which are olif-center with respect to the center of curvature for the outer surface of the body.

Between the overlapping parts of the body portions I3 of the members 'I0 and II are longitudinally spaced pairs of coacting friction blocks or shoes I'l-I8 respectively, of substantially the same shape and form. Each shoe has a longitudinal outer tapered surface I9 that fits the taperof associated surfaces I4 and I5 respectively, a transverse end surface 20 and a diagonal 50 friction surface 2|. Each shoe II is formed with an arcuate extension IIa` on its end 20 and this extension materially increases the area of the surface I9. One of the shoes Il is shown in perspective in Fig. 5. Each shoe I8 is formed at that 55 end opposite its end I9 with a shoulder IBa for l engagement with an associated shoulder I5 to provide a stop that defines the normal positions of the members III and II, when not under load, as shown in Fig. 1.

Between the surfaces 2I-2I of the shoes of each pair is located a plate 22 of metal or other suitable material. By means of this plate, the superficial frictional contact or engagement between the shoes of each pair is substantially doubled. In the shoes of each pair, as well as in the plate 22 associated therewith, is a longitudinal opening 23. Y

A retainer bolt 2d of a diameter somewhat less than the diameter of the openings 23, extends through said openings in the blocks or shoes of both pairs and through the associated plates 22 thereof so as to permit some lateral movement between the shoes or blocks of each pair. Said bolt, which is of a length to extend through the blocks of both pairs, has a head 25 at one end engaged with the transverse end face 2|] of the block I1 of one pair of blocks. The other end of the bolt carried a nut 26 engaged with the transverse end face 20 of the block I1 of the other pair of blocks. A spring 21 is interposed between the opposed end faces of the blocks I8 of both pairs and which spring surrounds that part of the bolt between said pairs of blocks.

A main compression resistance and release spring 28 of helical formation surrounds the body portion i3 of both the members IQ and il' and has direct engagement atY its'ends with the iianges I2 of said members. This spring has an internal diameter providing a relatively snug fit upon the Vcuter surfaces of said overlapping body portion I3 of both members Ill-II and has an external diameter approximating that ofthe said flanges I2. Preferably, the spring 28 is -made from octagcnal bar stock.

In the assembly of the device the nut 26 is screwed down tight to bring the various convolutions of the spring 21 into engagement to .make the spring go` solid, after which the nut is backed off for about two turns. This will open up the convolutions of the spring to an amount which provides for the necessary relative movement between the friction `blocks or shoes. Thus the spring 21 is employed to establish an initial pressure for said blocks or shoes and maintains them in initial pressure condition, the end of the bolt associated with the nut 26 being upset to prevent unscrewing of the nut.

In Fig. 1 the parts are shown in their normal non-load bearing or pressure receiving position. When a load or pressure is imposed upon one or the other of the fianges I2-I2 of the members I and I I in the relative movement of said members toward'each other, the spring 28 is placed under compression and at theV same time the friction grip is increased not only between the blocks I2v and I8 and thesurfaces I5 and I4 of the bodies of the members II] and II, but also between the blocks I1 and I8 themselves through the direct engagement of their diagonal surfaces 2l with the plate member 22. The frictional engagement of the sur-face I3 of `the members yIl! and II, respectively, with the flat inner surfaces of the convolutions of the springs 28, aids in increasing this grip. 'Ihis snubs the shock of compression under load. In this action the blocks I1 and I8 move relatively axially :and laterally the `enlarged opening 23 before-mentioned, .permitting the lateral lmovement, and the spring 21 compressing to permit the axial movement.

So soon as the load or pressure which has compressed the device has been removed, the spring 28 expands to immediately return the members III and IIV to their normal positions independently of the pairs of friction elements I1 and I8. In this way the return of the members ID and II to normal position is not accomplished through the friction element, but only through the spring 30. When said members have thus returned to normal position, the spring 21, which has been placed under compression by the relative movement of the blocks I1-I8, reexpands -to return the blocks to the normal Y positions wherein parts I8a ofthe blocks I8--I8 of both pairs engage against the stop shoulder lr6 on said members ID and II.

With the cushioning device made as described, it more nearly approaches uniformity of frictional resistance throughout and the tendency to bind or remain compressed under load is avoided. Therefore, upon release of load, the parts instantly return to normal position and this return is afforded through the spring 28 and not though the friction mechanism. By the proviion of the parts more directly associated with the pairs of friction blocks or shoes, it is possible to establish and maintain said blocks or shoes in initial pressure condition.

While in describing the invention, I have referred in detail to the `form and arrangement of the Aparts of the device, the same is to be considered only in the illustrative sense, so that I do not wish to be limited thereto except as may be specifically set forth in the appended claims.

I claim as my invention:V I

1. In a cushioning device for railway cars, the combination of two members that are relatively movable toward and away from each other and each of which includes a body portion having a plurality of longitudinally spaced, tapered in- .ternal Vfriction surfaces, said members being arranged with Vtheir body portions in end to end overlapping relation so that the friction surfaces of one body portion are opposed to those of the other body portion, means providing a plurality of longitudinally spaced, friction mechanisms disposed between said body portions so as to engage said opposed friction surfaces thereof, and resilient means engaging portions of both members and cooperating with said friction mechanisms in olfering a resistance to the relative movement of said members, toward each other.

2. Ina cushioning device for railway cars, the combination of two members that are relatively movable toward and away from each other and each of which includes a body portion having a plurality of longitudinally spaced, tapered internal 'friction surfaces, lsaid members being arranged with their body portions in end to end overlapping relation sothat the friction surfaces of one body portion are opposed to those of the other body portion, means providing a plurality of longitudinally spaced friction mechanisms disposed between said body portions so as to :engage said opposed friction surfaces thereof, resilient means engaging portions of both members and cooperating with said friction mechanisms in offering a'resistance to a rela- `tive lmovement of said members toward each other, and means carried by said body portions and engageable by said mechanisms for limiting the Vrelative movement of said members away from each other.

3. In a cushioning device for railway cars, the combination of two members that are relatively movable toward and away from each other and each of which includes a body portion having a plurality of longitudinally spaced, tapered internal friction surfaces, Vsaid members being arranged with their body portions in end to end overlapping relation so that the friction surfaces of one body portion are opposed to those of the other body portion, means providing a plurality n of longitudinally spaced friction mechanisms arranged between said body portions, each mechanism including a plurality of coacting friction blocks which are frictionally engaged with associated friction surfaces of said body portions and with each other, and resilient means engaging portions of both members and cooperating with said friction mechanisms in offering a resistance to the relative movement of said members toward each other. l

4. In a cushioning device for railway cars, the combination of two members that are relatively movable toward and away from each other and each of which includes a body portion having a plurality of longitudinally spaced, tapered internal friction surfaces, said members being arranged vnth their body portions in end to end overlapping relation so that the friction surfaces of one body portion are opposed to those of the other bodyv portion, means providing a plurality of longitudinally spaced friction mechanisms arranged between said body portions, each mechanism including a pair of coacting blocks having external surfaces for engagement with associated surfaces of both body portions and having diagonal frictionsurfaces facing each other, and resilient means engaging portions of both members and cooperating with said friction mechanisms in offering a resistance to the relative movement of said members toward each other.

5. In a cushioning device for railway cars, the combination of two members that are relatively movable toward and away from each other and each of which includes a body portion having a plurality of longitudinally spaced, tapered internal friction surfaces, said members being arranged with their body portions in end to end overlapping relation so that the friction surfacesy of one body portionare opposed tothose of the other body portion, means providing a plurality of longitudinally spaced friction mechanisms arranged between said body portions, each mechanism including a plurality of coacting friction blocks which are frictionally engaged with associated friction surfaces of said body portions and having diagonal friction surfaces that are opposed to each other, resilient means engaging portions of both members and cooperating with said friction mechanisms in offering a resistance to the relative movement of said members toward each other, means for urging said friction mechanisms into tighter engagement with the associated surfaces of said body portions and for urging the friction blocks in each mechanism into tighter engagement with each other, and means for limiting the movement of said mechanisms away from each other.

6. In a cushioning device for railway cars, the combination of two members that are relatively movable toward andY away from each other and each of which includes a body portion having a plurality of longitudinally spaced, tapered internal friction surfaces, said members being arranged with their body portions in end to end overlapping relation so that the friction surfaces of one bodyportion are opposed to those of the other body portion, means providing a plurality of longitudinally spaced friction mechanisms arranged between said body portions, each mechaknism incdluding a plurality of coacting friction blocks which are frictionally engaged with associated friction surfaces of said body portions and having diagonal friction surfaces that are opposed to each other, resilient means engaging portions of both members and cooperating with said friction mechanisms in offering a resistance to the relative movement of said members toward each other, means for urging said friction mechanisms into tighter engagement with the associated surfaces of said body portions and for urging the friction blocks in each mechanism into tighter engagement with each other, and means extending through the blocks of both friction mechanisms for limiting the movement Vof said mechanisms away from each other.

7. In a cushioning device for railway cars, the combination of the members that are relatively movable toward and away from each other vand each of which includes a body portion having a pair of longitudinally extending internal friction surfaces arranged tandem fashion, said members being arranged with their body portions in overlapping end to end relation so that the pair of friction surfaces on one body portion are opposed to those on the other body portion, means providing a pair of longitudinally spaced friction mechanisms disposed between said body portions and engaged with the associated opposed friction surfaces of said body portions, and resilient means engaging portions of both members and cooperating with said friction mechanisms in offering resistance to the relative movement of said members toward each other.

8. In a cushioning device for railway cars, the combination of two members that are relatively movable toward and away from each other, each member including a longitudinal body portion with a radial flange at one end, and a pair of longitudinally extending internal friction surfaces arranged tandem fashion, said members being arranged with the other ends of said body portions in overlapping relation so that the f riction surfaces of one body portion are opposed to those of the other body portion, meansv providing a pair of longitudinally spaced friction mechanisms disposed between said body portions, and resilient means surrounding both body portions and engaged with the radial flanges of both of said members and cooperating with said friction mechanisms in offering resistance tothe relative movement of said members toward each other.

9. A member for use in a cushioning device of the kind described and comprising a longitudinal body portion having an outwardly extending radial flange at one enddening a central opening for said end of the member, said body portion having a plurality of longitudinally tapered internal friction surfaces arranged tandem fashion,

land means providing a stop shoulder for that 

